Project summary/abstract Behavioral weight loss (WL) programs result in clinically significant weight losses; however rates of long-term WL maintenance are poor. Previous studies suggest that long-term WL success may require an enhanced ability to overcome physiological and hedonic urges to eat and an improved capacity for dealing with life stressors, negative mood states, and food cravings. Thus interventions which target stress reduction and reduce the tendency to use food as a coping strategy for aversive experiences may offer a protective effect against dietary lapses; thereby improving long-term WL outcomes. Yoga is a mind-body intervention which reduces stress and improves overall physical and psychological well-being and offers promise for strengthening the psychological skill set needed for maintaining important weight-related behaviors long-term. The physical and cognitive skills practiced within yoga target multiple underlying psychological processes (e.g., mindfulness, distress tolerance) which could reduce emotional eating, improve dietary choices, and enhance one's ability to tolerate food cravings or hedonic urges to eat. While yoga is an effective treatment approach for other chronic health conditions, it has not been examined as a potential intervention for improving long-term WL outcomes. Within the context of the obesity field, yoga has been viewed as a mode of exercise and not necessarily as a mind-body intervention approach (as is the case in other fields). Thus, given the lower caloric expenditure of yoga in comparison to many forms of aerobic exercise, the effect of yoga on important weight- related processes and behaviors has not been examined. This study aims to examine the feasibility and acceptability of implementing yoga within a weight management program and to examine the impact of yoga, relative to a contact-control condition (CON), on important psychological constructs and weight-related behaviors. Sixty women with a BMI of 25-40 kg/m2 will be randomly assigned to a 12-week standard behavioral WL program, followed by either 12 weeks of group-based yoga or 12 weeks of cooking/dietary information classes. Both groups will be instructed to self-monitor and achieve the dietary and aerobic exercise goals throughout the 24-week program. Assessments will occur at baseline and weeks 12 and 24. Attendance and program satisfaction with the yoga intervention will be assessed. YOGA and CON will be compared on general (perceived stress, mindfulness, distress tolerance), and eating-specific variables (hedonic, emotional, and mindful eating) assessed via questionnaire, and by ecological momentary assessment (EMA). EMA will be used to capture dietary temptations, cravings, and dietary lapses, as they occur in real-time via smartphones; objective physical activity monitors will examine whether levels of aerobic exercise differ between YOGA and CON. Treatment groups will be compared on 12-24 week changes in weight. These preliminary findings can be used to inform future research efforts on the efficacy of yoga, an example of a mind-body intervention for WL maintenance, and the psychological mechanisms through which yoga may influence body weight.